Company-Owned Life Insurance (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Schedule of Company - Owned Life Insurance, By Type
Total	$ 502.4	$ 497.9
Key executive, principal shareholder
Schedule of Company - Owned Life Insurance, By Type
Cash surrender value of life insurance	1.8	3.2
Key executive split dollar
Schedule of Company - Owned Life Insurance, By Type
Cash surrender value of life insurance	5.0	7.1
FIB \| Group life
Schedule of Company - Owned Life Insurance, By Type
Cash surrender value of life insurance	$ 495.6	$ 487.6

[Line Items] for Schedule of Company - Owned Life Insurance, By Type [Table]

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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

+ Details

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- Definition

This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 325
-SubTopic 30
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481612/325-30-25-1

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